Micrometer setting device



Feb. 27, 1951 I. SWIDLER MICROMETER SETTING DEVICE Filed Feb. 4, 1946 IN VEN TOR. /6/00RE SW/OLE/a Patented Feb. 27, 1951 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928; 3'70 0. G. 757) 1 Claim.

This invention relates to a micrometer-setting device and more specifically to an attachment for accurately setting the adjustable anvil of an arch micrometer.

An object of this invention is to provide an attachment for aiding in accurately setting the adjustable anvil of an arch micrometer with respect to the spindle.

A further object is to provide an attachment adapted to clamp on the outer end of an arch micrometer and impart a finely-controlled movement to the adjustable anvil for accurate adjustment relative to the zero setting of the spindle thimble adjustment.

A further object is to provide a device that facilitates the use of an arch micrometer to accommodate different sizes of work by accurately setting the gap between the adjustable anvil and the zero setting of the movable spindle, the micrometer readings being limited to one or two inches while the span of the arch or frame can be four to twelve inches or more.

Further objects and advantages of this invention, as well as its construction, arrangement and operation are apparent from the following description and. claim in connection with the accompanying drawings, in which:

Fig. 1 is a front elevational view of a preferred embodiment of the present invention.

Fig. 2 is an end elevational view of the device shown in Fig. 1.

A preferred form of the micrometer setting device II is shown attached to an arch micrometer l2 having a thimble l3 at one end and an adjustable anvil M at the other end.

The adjustable anvil I 4 is slidably mounted in a bore in one end of the frame l2 and is secured in a selected position by the setscrew [6. The setting device is clamped to one end of the frame l2 by means of a U-shaped clamp having furcated arms l1 and I8, and a threaded clamping handle I9 on the arm II. Between arms ll and I8 is a crosspiece having a bore [9 to which is rotatabl connected a cylindrical member having 2. depending ear 2! with a bore 22. A nut and bolt assembly 23 pass thru the bores l9 and 22 thus rotatably connecting the furcated clamp and the cylindrical member 20.

The cylindrical member 20 has internal threads 24 engaged by the threaded bushing 25. The

threaded bushing 25 has a hexagonal head 26 at the outer end and a bore 21 adapted to receive for sliding the adjustable anvil l4. A threaded clamp handle 28 clamps the anvil M in position within the bushing 25.

In operation, when it is desired to set the anvil M to accommodate any particular work such as pieces varying in size from four to five inches, the micrometer thimble l3 associated with spindle 29 is set at zero and the setting device H is attached to the opposite end of frame [2. With the setscrew l6 loose the anvil I4 is slid thru the bore 21 in bushing 25 until the gap between the micrometer spindle 29 and the adjustable anvil I4 is slightly more than four inches.

The clamping handle 28 is tightened and a gage measuring exactly four inches is placed between the anvil and the spindle. A wrench is used on the hexagonal head 26 to rotate and move the bushing 25 inwardly. This slowly moves the adjustable anvil l4 inwardly until the end just touches the four inch gage. When the gap is accurately set at four inches the set screw it is tightened and the setting device H is removed. The arch micrometer can now be used to make accurate measurements from four to five inches.

The setting device II is used in a similar manner to make any settings within the range of the particular arch micrometer to which it is attached.

It is to be understood that various modifications and changes may be made in this invention without departing from the spirit and scope thereof as set forth in the appended claim.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

In a micrometer a frame, said frame having therethrough a cylindrical bore with an axis, a clamp, means for detachably mounting said clamp on said frame adjacent said bore, a boss mounted on said clamp for swinging movement about an axis parallel to said bore axis, said boss having a bore axially alignable with said frame bore, said boss bore being larger than said frame bore and threaded, an externt 11y threaded bush- 3 4 ing in the threaded boss here for screvving move- REFERENCES CITED ment along the bore axls sald bushmg havmg The following references are of record in the therethrough a bore of substantially the same diameter as the frame bore and coaxial with the file of thls patent boss bore, a cylindrical anvil freely slidably 5 UNITED STATES PATENTS mounted in the bushing and frame bores, screw Number Name Date means in said frame for releasably locking said 363,554 spaulding Aug 16, 1887 anvil in said frame, and screw means in said 438,733 Tansley Oct. 21 1890 bushing for releasably locking said anvil in said 1,254,218 Eskelinen Jan 1918 bushing. 10 1,291,211 Slocomb Jan. 14: 1919 ISJDORE SWIDLER- 1,425,201 Hetherington Aug. 8, 1922 1,475,066 Gregory Nov. 20, 1923 

